1. Field of the Invention
The present general inventive concept relates to a display apparatus and a control method thereof, and more particularly, to a display apparatus and a control method thereof, in which an auto-adjustment function is performed according to display modes of an input video signal.
2. Description of the Related Art
Generally, a display apparatus receives a video signal of a predetermined display mode from a video signal source, such as a computer, a television broadcasting system, etc., thereby displaying a picture on a screen thereof. Such a display apparatus has been developed, that is, a cathode ray tube (CRT) has been replaced with a flat panel display, such as a liquid crystal display (LCD), a plasma display panel (PDP), etc.
As compared with a CRT type display apparatus, a flat panel display apparatus receives an analog video signal from a video signal source and converts the analog video signal into a digital video signal, thereby displaying a picture. Here, the flat panel display apparatus comprises an analog/digital (A/D) converter to convert the analog video signal into the digital video signal. Further, the digital video signal converted by the A/D converter is processed by a preset method and transmitted to an LCD panel or the PDP, thereby driving a pixel corresponding to the digital video signal and displaying the picture.
Meanwhile, a recently developed display apparatus has an additional function to change a display mode thereof properly when a resolution of the analog video signal is changed, which will be generally called an auto-adjustment function.
For example, the display mode of the video signal transmitted from the video signal source, such as a computer or the like, includes various resolutions of 640×480 at 60 Hz; 640×480 at 75 Hz; 800×600 at 60 Hz; 1024×768 at 60 Hz; 1600×1200 at 60 Hz; 1920×1200 at 60 Hz; and so on. Here, when the video signal having a resolution of 640×480 at 75 Hz is transmitted from the video signal source to the display apparatus being set to have the display mode based on a resolution of 1024×768 at 60 Hz, that is, when the resolution of the input video signal does not match the display mode of the display apparatus, the picture is not optimally displayed. Therefore, the auto-adjustment function compensates for a difference between the display mode of the display apparatus and the resolutions of the input video signal, thereby allowing the display apparatus to optimally display the picture according to the video signal.
Further, an auto-adjustment button is generally provided in a front of the display apparatus and used for performing the auto-adjustment function.
Also, there has been developed a display apparatus continuously applying the auto-adjustment function to the input video signal.
However, in a case of the display apparatus performing the auto-adjustment function using the auto-adjustment button, a user unskilled in the display apparatus is likely to misunderstand that a problem arises not in the display apparatus but in the video signal source, such as a computer, when a picture is not optimally displayed, e.g., when a position of a picture is moved to one side because the resolution of the input video signal does not match the display mode of the display apparatus.
Further, in a case of the display apparatus set to continuously apply the auto-adjustment function to the input video signal, the auto-adjustment function is performed even when the video signal outputted from the video signal source is temporarily changed in the display mode, e.g., in a case where the video signal provided during a booting process of the computer is different in the display mode from the video signal provided by an operating system of the computer. Thus, a user unskilled in the display apparatus is likely to regard alteration in a picture arising while the auto-adjustment function is performed, as an error occurring in the display apparatus or the computer. Particularly, in a case of the computer, the video signal provided during the booting process of the computer is very different in the resolution from the video signal provided by the operating system. Further, the video signal provided during the booting process of the computer has a lot of black regions, so that it is difficult to apply the auto-adjustment function to this video signal, so that the user is more likely to misunderstand that the computer or the display apparatus is in trouble.